Engineering
Two researchers at the Chinese University of Hong Kong have developed a new membrane design that prevents crossover in polysulfide redox flow batteries. In their paper published in the journal Nature Energy, Zhejun Li and ...
Engineering
With the ever-increasing worldwide mass production of plastic, the inefficiency of current plastic recycling strategies has raised several environmental, societal, and economic concerns. Magnetic density separation (MDS) ...
Feb 26, 2021
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322
Engineering
With the growth of 3-D printing, it's entirely possible to 3-D print your own prosthetic from models found in open-source databases.
Apr 4, 2019
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177
Energy & Green Tech
In remote areas of the world or in regions with limited resources, everyday items like electrical outlets and batteries are luxuries. Health care workers in these areas often lack electricity to power diagnostic devices, ...
Aug 19, 2018
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65
Energy & Green Tech
In a world where rising temperatures increase the demand for cooling, traditional air conditioning (AC) systems contribute significantly to global energy consumption. They also heat Earth overall: to cool down a certain volume ...
Apr 10, 2024
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1
Engineering
A research team has developed a human lung-inspired graphene-metal organic framework hybrid gas sensor, which can monitor extremely low concentrations of nitrogen dioxide at the level of one billionth in real-time. This study ...
Jul 6, 2023
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3
Engineering
Wherever electric motors or electromagnets are too large or too heavy to be incorporated into a technical component, the novel drive mechanisms being developed by a research team led by Professors Stefan Seelecke and Paul ...
Apr 5, 2023
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32
Electronics & Semiconductors
Professors Stefan Seelecke and Paul Motzki at Saarland University are developing intelligent materials that are opening up new avenues in sound reproduction technology: lightweight loudspeakers that use far less energy than ...
Apr 4, 2023
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3
Energy & Green Tech
Modern energy storage systems are an important building block for a climate-friendly future. "Modern" means not only that their performance meets the demands of a high-tech society, but also that they can be produced and ...
Mar 27, 2023
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Energy & Green Tech
Aviation is a big user of fossil fuels and, as such, is a heavy producer of carbon emissions. Sustainability is high on the agenda. New work in the International Journal of Sustainable Aviation has reviewed the thermo-physical ...
Nov 7, 2022
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Surface area is the measure of how much exposed area a solid object has, expressed in square units. Mathematical description of the surface area is considerably more involved then the definition of arc length of a curve. For polyhedra (objects with flat polygonal faces) the surface area is the sum of the areas of its faces. Smooth surfaces, such as a sphere, are assigned surface area using their representation as parametric surfaces. This definition of the surface area is based on methods of infinitesimal calculus and involves partial derivatives and double integration.
General definition of surface area was sought by Henri Lebesgue and Hermann Minkowski at the turn of the twentieth century. Their work led to the development of geometric measure theory which studies various notions of surface area for irregular objects of any dimension. An important example is the Minkowski content of a surface.
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